Global Patent Index - EP 2028285 A1

EP 2028285 A1 20090225 - HIGH CLEANLINESS SPRING STEEL AND HIGH CLEANLINESS SPRING EXCELLENT IN FATIGUE CHARACTERISTICS

Title (en)

HIGH CLEANLINESS SPRING STEEL AND HIGH CLEANLINESS SPRING EXCELLENT IN FATIGUE CHARACTERISTICS

Title (de)

HOCHREINER FEDERSTAHL UND HOCHREINE FEDER MIT HERVORRAGENDEN ERMÜDUNGSEIGENSCHAFTEN

Title (fr)

ACIER À RESSORT À PROPRETÉ ÉLEVÉE ET RESSORT À PROPRETÉ ÉLEVÉE AYANT DES CARACTÉRISTIQUES EXCELLENTES DE FATIGUE

Publication

EP 2028285 A1 20090225 (EN)

Application

EP 07743972 A 20070523

Priority

  • JP 2007060538 W 20070523
  • JP 2006160796 A 20060609
  • JP 2006161240 A 20060609

Abstract (en)

High cleanliness spring steel useful in manufacturing a spring with SiO 2 -based inclusions being extremely controlled and excellent in fatigue properties is provided. High cleanliness spring steel which is steel containing; C: 1.2% (means mass%, hereafter the same with respect to the component) or below (not inclusive of 0%), Si: 1.2-4%, Mn: 0.1-2.0%, Al: 0.01% or below (not inclusive of 0%), and the balance comprising iron with inevitable impurities, wherein; the total of oxide-based inclusions of 4 or above of L (the large diameter of an inclusion)/D (the short diameter of an inclusion) and 25 µm or above of D and oxide-based inclusions of less than 4 L/D and 25 µm or above of L, in the oxide-based inclusions of 25 mass% or above of oxygen concentration and 70% (means mass%, hereafter the same with respect to inclusions) or above of SiO 2 content when Al 2 O 3 + MgO + CaO + SiO 2 + MnO = 100% is presumed, out of inclusions in the steel, is 20 nos./500 g or below.

IPC 8 full level

C22C 38/00 (2006.01); C21D 7/04 (2006.01); C21D 7/06 (2006.01); C22C 38/02 (2006.01); C22C 38/04 (2006.01); C22C 38/06 (2006.01); C22C 38/08 (2006.01); C22C 38/12 (2006.01); C22C 38/18 (2006.01); C22C 38/24 (2006.01); C22C 38/28 (2006.01); C22C 38/34 (2006.01); C22C 38/40 (2006.01); C22C 38/44 (2006.01); C22C 38/46 (2006.01); F16F 1/02 (2006.01)

CPC (source: EP KR US)

C21D 7/04 (2013.01 - EP KR US); C21D 7/06 (2013.01 - EP KR US); C22C 38/002 (2013.01 - EP US); C22C 38/005 (2013.01 - EP US); C22C 38/02 (2013.01 - EP US); C22C 38/04 (2013.01 - EP KR US); C22C 38/06 (2013.01 - EP KR US); C22C 38/08 (2013.01 - EP KR US); C22C 38/12 (2013.01 - EP KR US); C22C 38/18 (2013.01 - EP KR US); C22C 38/24 (2013.01 - EP KR US); C22C 38/28 (2013.01 - EP US); C22C 38/34 (2013.01 - EP KR US); C22C 38/40 (2013.01 - EP KR US); C22C 38/44 (2013.01 - EP US); C22C 38/46 (2013.01 - EP KR US); F16F 1/021 (2013.01 - US); C21D 2211/004 (2013.01 - EP US)

Designated contracting state (EPC)

AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU LV MC MT NL PL PT RO SE SI SK TR

Designated extension state (EPC)

AL BA HR MK RS

DOCDB simple family (publication)

EP 2028285 A1 20090225; EP 2028285 A4 20110420; EP 2028285 B1 20160323; BR PI0712343 A2 20120131; BR PI0712343 B1 20140902; EP 2407571 A2 20120118; EP 2407571 A3 20120125; EP 2407571 B1 20160330; KR 101056868 B1 20110812; KR 101106871 B1 20120119; KR 20090010231 A 20090129; KR 20110008347 A 20110126; US 2009194204 A1 20090806; US 2010111748 A1 20100506; US 2015118097 A1 20150430; US 8613809 B2 20131224; US 9441695 B2 20160913; WO 2007142034 A1 20071213

DOCDB simple family (application)

EP 07743972 A 20070523; BR PI0712343 A 20070523; EP 11008110 A 20070523; JP 2007060538 W 20070523; KR 20087029877 A 20070523; KR 20117000857 A 20070523; US 201514593581 A 20150109; US 30154407 A 20070523; US 68367210 A 20100107